High voltage ignition wire

ABSTRACT

An improved high voltage ignition wire structure including a central conductor surrounded by insulation with at least one electrically conducting sheath about such insulation extending a part of the length of the wire and electrically connected to the central conductor at only one end thereof. A materially increased voltage output appears at the wire end for application of the same power input.

United States Patent Lonnie R. Capehart 305 W. Standley Ave., Ukiah, Calif. 95482 807,257

Mar. 14, 1969 Jan. 5, 1971 lnventor Appl. No. Filed Patented HIGH VOLTAGE IGNITION WIRE 6 Claims, 4 Drawing Figs.

U.S. Cl 174/36, 338/64, 338/66 Int. Cl. I-l0lb 11/06 Field of Search 338/64, 66,

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[56] References Cited UNITED STATES PATENTS 2,790,053 4/1957 Peterson 338/214X 3 ,469,0 l 6 9/1969 Shelton l. 174/36 Primary Examiner-E. A- Goldberg AnorneyGregg and Hendricson ABSTRACT: An improved high voltage ignition wire structure including a central conductor surrounded by insulation with at least one electrically conducting sheath about such insulation extending a part of the length of the wire and electrically connected to the central conductor at only one end thereof. A materially increased voltage output appears at the wire end for application of the same power input.

Certain conventional classes of internal combustion engines rely upon the generation of the spark to ignite the fuel for combustion. These types of engines as are widely employed, for example, for automotive and marine propulsion, incorporate an electrical system including a battery and a generator or alternator driven by the engine during operation of the latter and producing high voltage spark discharges in timed sequence in engine cylinders. This high voltage is normally achieved through the use of a capacitor and coil wherein the relatively low voltage output of the generator or alternator is converted to a high voltage and low current for application to a distributor which appropriately applies this high voltage energization to the separate spark plugs of the engine. In optimization of operation of this type of engine many improvements have been made in the field of distributors and coils. Of particular interest to many automotive engineers is the advantage to be gained by increasing the spark plug discharge voltage and various improved coil structures have been advanced for this purpose. Commonly, however, these heavy duty coils, as they are often termed, serve to increase the amperage of the discharge with the resultant burning of distributor contacts and spark plug electrodes. Additionally it is recognized that heavy duty coils are quite expensive.

In addition to the basic engineering approaches to improvements in the operation of internal combustion engines, there have been developed innumerable gadgets which may be employed as accessories in the electrical system of automobiles in particular. Various of these devices are intended to provide a hotter spark but tests fail to show that these results are achieved.

It is generally recognized that improved fuel combustion in an internal combustion engine is highly advantageous and much to be desired. Not only is it possible to improve engine efficiency in this manner in order to reduce fuel consumption but also it is possible to increase engine output. Further, and of particular importance at the present time, is the possibility of decreasing engine exhaust pollutants. The problem of smog or air pollution resulting from automotive engine exhausts has received widespread attention and suggested solutions to the problem have varied from afterbumers to complicated exhaust systems and even to the banning of operation of this type of engine. Improved combustion of fuel employed in internal combustion engines clearly reduces the percentage of contaminants exhausted from the engine and, thus, will provide at least a partial solution to the present problem of automotive air pollution.

The present invention provides an improved ignition wire or conductor operable upon substantially any type of internal combustion engine employing a spark to initiate combustion. No modification of existing engines is required and while the conductor of this invention may be employed at various places in the ignition system it is most readily utilized as a replacement for the conventional conductor between coil and distributor of the engine. With no other modification of the electrical system of a conventional engine the present invention will very materially increase the spark discharge voltage to improve horsepower and torque output, decrease fuel consumption and decrease the percentage of exhaust contaminants.

SUMMARY OF INVENTION The present invention provides an extremely simple conductor structure embodying, in addition to an insulated central wire or conductor, at least one surrounding electrical conductor exteriorly of such insulation, connected to the central conductor at one end thereof and extending a part of the length of the central conductor. The invention operates to not only connect the voltage applied at one end to means connected at the other end but also to induce a voltage in the outer conductor and add same to the output voltage.

Structurally the present invention may closely resemble conventional shielded ignition wires with the limitation, however, that the shield shall not be grounded and furthermore that it shall connect to the central conductor only at one end of the overall unit. It shall be insulated from and substantially displaced from the central conductor at the opposite end of the unit.

DESCRIPTION OF FIGURES The present invention as illustrated as to a single preferred embodiment thereof in the accompanying drawing wherein:

FIG. 1 is a shortened plan view of an ignition wire in accordance with the present invention;

FIG. 2 is a transverse sectional view taken in the plane 2-2 of FIG. 1;

FIG. 3 is a central longitudinal sectional view taken through the ignition wire of FIGS. 1 and 2; and

FIG. 4 is a schematic illustration of the ignition wire of the present invention in use connecting the coil and distributor of an engine.

DESCRIPTION OF PREFERRED EMBODIMENT The ignition wire of the present invention basically comprises an insulated conductor adapted to carry high voltage low current pulses of electrical energization as employed in the high voltage ignition portion of the electrical wiring system for an internal combustion engine or the like. Although the present invention may be otherwise applicable, i.e., marine, stationary industrial, racing and other engines, it is herein described in connection with conventional automobile engines. It is further noted that the present invention is herein. shown and described with one outer conductor, however, two or more may be employed with each being radially displaced and insulated from each other along same to further increase voltage output.

Referring to FIGS. 1, 2 and 3 of the drawing it will be seen that the ignition wire, of unit 11, is comprised of a central metal conductor 12 preferably formed of copper or the like, or other materials, such as the common resistor-type conductor so as to incorporate a certain flexibility, and surrounded by a layer of insulation 13. In accordance with conventional practice there may be provided a connector 14 formed of metal and enveloping at least a part of a first end of the unit. This connector 14 may be formed as a short U-shaped metal piece having inwardly turned ends clamping the insulation 13 and soldered to the central conductor 12 as indicated at 15. The connector 14 electrically contacts the central conductor 12 and thiscontact may be enhanced by the provision of one or more internal projections 16 extending along and in contact with the end of the central conductor 12. The connector construction may be quite conventional and is adapted for substantially permanent engagement with the .end of the ignition wire to provide a connector for engaging this first end of the wire with some unit in the ignition system.

The ignition wire of the present invention as illustrated further includes an electrically conducting sheath 17 disposed about the insulating layer 13 in contact therewith. This sheath 17 extends from a second end of the unit or ignition wire, as shown, along the length thereof to terminate a substantial distance from the first end. The sheath 17 may be formed of wire braid and to this extent may appear somewhat as a conventional conductor shield oftentimes employed for the purpose of reducing radio interference from ignition wiring. in the present invention, however, it is particularly noted that the sheath 17 does not extend the full length of the unit or ignition wire but instead is terminated short of one end thereof. An outer electrical insulator 18 formed, for example, of rubber, plastic or the like, is disposed about the sheath l7 and extends toward the connector 14 from adjacent the second end of the wire, as illustrated, for example, in FIG. 3 of the drawing. Both of the insulators 13 and 18 may be formed of a flexible insulating material such as rubber or the lik'e, so that the entire ignition wire unit has a certain flexibility. The outer insulating layer 18 tightly fits the remainder or internal portion of the unit so as to be in intimate contact with the sheath 17 and also in contact with the inner insulating layer 13 for a distance past the end ofthe sheath 17 toward the first end of the wire, as shown.

The present invention further provides that the central conductor 12 and electrically conducting sheath 17 are joined together atthe second end of the ignition wire or unit opposite from the connector 14. This is illustrated in FIG. 3 by the metal connection 19 extending across the end of the unit between the central conductor 12 and sheath 17. This metal connection 19 may in fact comprise a solder joint, if desired. Various alternative ways are available for electrically joining the central conductor and sheath at the second end of the unit. Whatever the type of joiner, it is necessary to the present invention that the central conductor and electrically conducting sheath be electrically joined only at the second end of the unit. In one embodiment of the present invention the outer insulating layer 18 may be terminated short ofthe second end of the unit to expose a portion of the sheath 17 as an electrical connector for this end of the unit. This structure is shown in FIG. 1. However, it is to be appreciated that a variety of different connector structures are possible for the ignition wire of the present invention. This also applies to the opposite or first end of the wire wherein there is shown the particular connector 14 purely as an example of construction.

Considering operation of the present invention it is noted that the unit 11 is adapted to be connected between two units or elements of an ignition system and to carry successive pulses of high voltage, low current electrical energization. For example, the ignition wire hereof may be connected between a coil 21 and distributor 22 in the ignition system of a conventional automobile engine, as illustrated in FIG. 4. As a high voltage pulse passes along the central conductor 12 of the unit it induces avoltage in the sheath 17. In accordance with the present invention this induced voltage is connected back to the central conductor at the second end of the unit by the electrical connection 19. Consequently the output voltage at the second end of the ignition wire unit is materially greater than would be the case in the absence of the sheath 17 and connection thereof to the central conductor. The induced voltage in the sheath is employed herein to increase the applied voltage from the conductonlt is necessary for the other end of the sheath 17 to be electrically insulated from the opposite end of the unit, which in the illustrated embodiment is the connector 14. By electrically floating the free end of the electrically conducting sheath the voltage induced therein travels along the sheath to the connection with the central conductor 12 and reinforces the voltage pulse passing through the central conductor. In practical application of the present invention it is necessary to provide a substantial isolation of the connector 14 and free end of the sheath in order to prevent sparking therebetween. The high voltages involved as, for example, of the order of 30 kilovolts, is sufficient to jump a substantial air gap and even to penetrate insulation if insufficient separation is not provided. With voltages of this sort it has been found normally sufficient to provide 2 or 3 inches separation between the connector 14 and the end of the sheath l7, and the insulation between these elements is further enhanced by the outer insulator l8 enveloping the free end of the sheath.

With regard to the application of the present invention as illustrated in FIG. 4, it is noted that a conventional system provides for the building up of a large voltage in the coil 21 and the closure of a contact in the distributor to discharge this voltage from the coil through the ignition wire 11 for distribution to separate spark plugs of the engine through the distributor. In practice the connector 14 of the illustrated ignition wire may be inserted in the conventional connector opening at the top of the coil 21 and usually an electrical boot is applied about this connection. The second end of the ignition wire whereat the sheath and central connector are connected together may be inserted in the conventional open connector aperture in the distributor 22. With the outer insulator I8 terminating short of the second end of the ignition-wire as illustrated in FIG. 1 the sheath itself may comprise the connector at this end of the ignition wire. In this respect it isnoted that the outer insulator 18 may have the end thereof-at the exposed portion of the sheath cupped, as illustrated at 23, so as to snugly fit the end of the wall about the'distributor connector aperture, although in general practice an additional rubber boot or cover is employed about this connection to prevent entrance of moisture, dirt or the like into the connection.

In practice, the ignition wire of the present invention may be constructed in accordance with relatively conventional techniques. The insulation 13 about the central conductor may be molded thereon and the wire braid of the sheath 17 slid on to this insulator in extension over most of the length thereof. In practice an ignition wire having the length of the order of 17 inches is satisfactory for substantially all conventional automobiles and the sheath may, as noted above,,.extend about 14 inches along such wire from the end thereof. A flexible outer insulator 18 of rubber or the like may be molded-or expanded and slipped over the remainder of the unit substantially to an end connector 14 to leave exposed a portion of the end of the sheath 17. The end connector 14 and central conductor 12 are electrically connected and the central'conductor and sheath soldered or otherwise electrically joined together at the opposite end of the unit.

One specific example of an ignition wire formed in accordance with the present invention and successfully used upon an automobile has a length of 22 inches with the outer braided conductor ending 2.5.inches from the first end and the insulation ending 1 inch from the second end. The center conductor is formed of 19 strands of wire to have an outer diameter of about 0.055 inch The insulation about the center wire is approximately 0.1 10 inch thick to thus have an outside diameter of about 0.275 inch. The outer conductor has a thickness of the order of 0.015 inch and the outer insulation a thickness of the order of 0.016 inch in the form of electrical insulating tape wrapped about the sheath. The outer diameter of the whole unit then is about 0.337inch. It is noted that good outer insulation is quite important to prevent high voltage discharge from the sheath to any adjacent metal.

While the ignition wire of the present invention has been described in connection with application between the coil and distributor of an automotive electrical wiring system it is to be understood that the ignition wire hereof may be otherwise em.- ployed in such an ignition system. It will be appreciated that high voltage for generating a spark in the cylinders of an internal combustion engine are also transmitted from the distributor to the spark plugs thereof. Thus the present invention may be employed as ignition wires from distributor to spark plugs. The increased output voltage from the ignition wire hereof, as noted above, will then be applied from distributor to spark plug. It is noted, however, that usage of the invention between distributor and spark plugs requires a plurality of such ignition wires while employment of the present invention as illustrated in FIG. 4 requires only one such wire of the present invention. It is further noted that the ignition wire hereof does not materially increase the amperage applied to the distributor and consequently does not result in burning of the contacts thereof. The voltage applied to the distributor through the present invention will be distributed to the separate spark plugs of the engine so as to establish a much higher sparkingvoltage thereat. This high voltage spark serves to more efficiently ignite and consequently burn fuel in the cylinders.

Tests have been made on all types of standard automobile engine coils, as well as special high-performance coils, in various automotive engines, first with standard coil wire and'then with the wire of the present invention installed, but with no other modification. Oscilloscope readings with the invention installed reflect that the voltage of the distributor is-doubled, without exception, with nodetrimental increase'in amperage. Dynomometer tests show, with the-present invention in place,

an increase horsepower, or foot pounds torque, for a given amount of fuel. Results of such tests show an increase of up to percent. Combustion analysis shows one to two points more complete combustion on a scale of 16 at a given or fixed engine r.p.m. under load and no load, and shows a lesser amount of fuel used. The fuel flow meter confirmed these tests simultaneously. The above results are highly advantageous for a variety of reasons.

The conventional ignition system as furnished on all standard engines was designed for the automobile of 1910. It was not designed for todays high speed, high compression engine and thus constant tuneups and repairs are required in order to obtain maximum performance. It is almost impossible for the modern engine to develop its highest potential horsepower using a conventional ignition system. The conventional ignition system does not provide sufficient voltage, resulting in missing, loss of power, carbon deposits, high fuel consumption and a rough-running engine.

With the present invention in place, increased voltage, more complete combustion and increased horsepower result. This largely eliminates problems with cold starting, starting of flooded engines, starting engines with fouled spark plugs, and

starting of worn engines. Also carbon deposits which occur upon spark plugs do not prevent proper spark generation with the high voltage generated through the ignition wire of the present invention. it is well-known thatspark plug gaps, i.e., the distance between spark plug electrodes, must be carefully adjusted for optimized engine operation, and yet, employing the ignition wire of the present invention, ithas been found that substantially no difference in engine operation can be detected even though the proper spark gap for a particular engine be increased by two fold.

in addition to the foregoing advantages a possibly less obvious advantage pertains which is of great importance to the general public. More complete combustion of fuel in internal combustion engines is achieved through utilization of the present invention, and this then means that exhaust from such engines is much cleaner and contains materially reduced percentages of pollutants or contaminants. With the present day interest in reducing air pollution, particularly from automobiles, the present invention then is particularly advantageous and engine exhaust analysis shows that the present invention actually accomplishes as much in the reduction of air pollution as highly complicated and expensive engine modifications and auxiliary equipment contemplated as possible solutions to the present problem of air pollution.

Although the present invention has been described above with respect to a single preferred embodiment thereof, it is be lieved evident that various modifications are possible within the teaching of the present invention. Consequently it is not intended to limit the present invention to the details of illustration and description. Reference is made to the appended claims for a precise delineation of the true scope of this invention.

lclaim:

1. An improved ignition wire comprising:

a central electrical conduction;

electrical insulation about said conductor with the conductor ends free for electrical contact; and

at least one electrically conducting sheath about said insulation extending into electrical contact with one end of said central conductor and terminating a distance from the other end of the central conductor for insulation therefrom.

2. The improved ignition wire of claim 1 further defined by an outer insulating cover about said sheath in enveloping relation to the unconnected end thereof.

3. The improved ignition wire of claim 2 further defined by said outer insulating cover terminating a short distance from the end of the sheath connected to the central conductor to expose a portion of said sheath thereat as an electrical contact.

4. The improved ignition wire of claim 1 further defined by 

1. An improved ignition wire comprising: a central electrical conduction; electrical insulation about said conductor with the conductor ends free for electrical contact; and at least one electrically conducting sheath about said insulation extending into electrical contact with one end of said central conductor and terminating a distance from the other end of the central conductor for insulation therefrom.
 2. The improved ignition wire of claim 1 further defined by an outer insulating cover about said sheath in enveloping relation to the unconnected end thereof.
 3. The improved ignition wire of claim 2 further defined by said outer insulating cover terminating a short distance from the end of the sheath connected to the central conductor to expose a portion of said sheath thereat as an electrical contact.
 4. The improved ignition wire of claim 1 further defined by a solder joint between said central conductor and said sheath at the connection therebetween.
 5. The improved ignition wire of claim 1 further defined by said sheath comprising flexible wire braid, and said central conductor and insulation being flexible.
 6. The improved ignition wire of claim 1 further defined by an electrically conducting connector secured about said insulation in engagement with said central conductor at the opposite end thereof from the connection of central conductor and sheath. 